Base station apparatus, terminal apparatus, and communication method

ABSTRACT

Provided are a base station apparatus, a terminal apparatus, and a communication method that achieve a radio access network capable of being flexibly compatible with various requirements. The base station apparatus according to an aspect of the present invention includes a transmission unit configured to generate a transmit signal based on a frame format in which a radio parameter is configurable, and configured to notify the terminal apparatus of information indicating the radio parameter configured in the frame format. The terminal apparatus according to an aspect of the present invention includes a reception unit configured to acquire information indicating a radio parameter configured in a frame format, and configured to demodulate a signal generated based on the frame format, based on the radio parameter.

TECHNICAL FIELD

The present invention relates to a base station apparatus, a terminalapparatus, and a communication method.

BACKGROUND ART

In a communication system such as Long Term Evolution (LTE) orLTE-Advanced (LTE-A) standardized by the Third Generation PartnershipProject (3GPP), the communication area can be widened by taking acellular configuration in which areas covered by base stationapparatuses (base stations, transmission stations, transmission points,downlink transmission devices, uplink reception devices, a group oftransmit antennas, a group of transmit antenna ports, componentcarriers, eNodeB, access points, APs) or transmission stationsequivalent to the base station apparatuses are arranged in the form ofmultiple cells (Cells) being linked together. Terminal apparatuses(reception stations, reception points, downlink reception devices,uplink transmission devices, a group of receive antennas, a group ofreceive antenna ports, UE, stations, STAs) are connected to the basestation apparatus. In such a cellular configuration, frequencyefficiency can be improved by using the same frequency among neighboringcells or sectors.

In LTE/LTE-A, frame formats are defined with respect to a frequencydivision duplex, a time division duplex, and a licensed assisted access,respectively. For example, the base station apparatus and the terminalapparatus of LTE/LTE-A using the frequency division duplex can alwayscommunicate using a common frame format without depending on acommunication bandwidth or the like.

Additionally, with the aim of starting a commercial service at around2020, research and development activities relating to a fifth generationmobile radio communication system (5G system) are actively performed.International Telecommunication Union Radio communications Sector(ITU-R) that is an international standardization organization recentlyreported a vision recommendation relating to a standard scheme of the 5Gsystem (International mobile telecommunication—2020 and beyond:IMT-2020) (see NPL 1).

In the vision recommendation, various use cases to which the 5G systemprovides a communication service are classified into three large usagescenarios (Enhanced mobile broadband (EMBB), Enhanced Massive machinetype communication (eMTC), Ultra-reliable and low latency communication(URLLC)). Additionally, the vision recommendation presents eight indexes(Peak data rate, User experienced data rate, Spectrum efficiency,Mobility, Latency, Connection density, Network energy efficiency, Areatraffic capacity) as requirements (Capabilities) of the 5G system.However, the vision recommendation also points out that, for the 5Gsystem, it is not necessary to simultaneously satisfy all therequirements, and it is sufficient to satisfy the requirements for eachof the usage scenarios. The requirements of each of the use cases/usagescenarios are of course different, and thus radio performance providedby a radio access network included in the 5G system is required todynamically change every moment.

CITATION LIST Non-Patent Literature

NPL 1: “IMT Vision—Framework and overall objectives of the futuredevelopment of IMT for 2020 and beyond”, Recommendation ITU-R M.2083-0,September 2015.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

However, in general, in a radio communication system, in view ofcomplexity of the system, a radio interface uses the common frame formatin many cases. In the existing LTE/LTE-A as well, one common frameformat is defined for each duplex scheme. However, by the common frameformat, there is a limit on the radio access network responding to therequirement that changes every moment. However, uselessly increasing thetypes of the frame format results in increasing the complexity of thesystem and overhead, and reducing the capability of the radio accessnetwork.

The present invention has been made in view of the above-describedcircumstances, and an object thereof is to provide a base stationapparatus, a terminal apparatus, and a communication method that achievea radio access network capable of being flexibly compatible with variousrequirements.

Means for Solving the Problems

To address the above-mentioned drawbacks, a base station apparatus, aterminal apparatus, and a communication method according to an aspect ofthe present invention are configured as follows.

(1) That is, a base station apparatus according to an aspect of thepresent invention is a base station apparatus for communicating with aterminal apparatus, the base station apparatus includes a transmissionunit configured to generate a transmit signal based on a frame format inwhich a radio parameter is configurable, and configured to notify theterminal apparatus of information indicating the radio parameterconfigured in the frame format.

(2) Additionally, a base station apparatus according to an aspect of thepresent invention is the base station apparatus according to theabove-described (1) in which the frame format may include a commonreference signal resource and a data signal resource, and the commonreference signal resource and the data signal resource may besequentially arranged in a time domain.

(3) Additionally, a base station apparatus according to an aspect of thepresent invention is the base station apparatus according to theabove-described (2) in which the transmission unit may generate thetransmit signal based on a frame format in which at least one resourceincluded in the frame format is subjected to aggregation in the timedomain or a frequency domain.

(4) Additionally, a base station apparatus according to an aspect of thepresent invention is the base station apparatus according to theabove-described (3) in which the transmission unit may provide anon-transmission section to the transmit signal generated based on theframe format including the aggregation.

(5) Additionally, a base station apparatus according to an aspect of thepresent invention is the base station apparatus according to any one ofthe above-described (2) to (4) in which the transmission unit mayselectively or simultaneously use a first frame format having adifferent resource arrangement from a resource arrangement of the frameformat and a second frame format being the frame format to generate thetransmit signal.

(6) Additionally, a base station apparatus according to an aspect of thepresent invention is the base station apparatus according to theabove-described (1) in which the radio parameter may include asubcarrier spacing.

(7) Additionally, a base station apparatus according to an aspect of thepresent invention is the base station apparatus according to theabove-described (3), the base station apparatus may transmit aconfiguration relating to the aggregation to the terminal apparatus.

(8) Additionally, a terminal apparatus according to an aspect of thepresent invention is a terminal apparatus for communicating with a basestation apparatus, the terminal apparatus includes a reception unitconfigured to acquire information indicating a radio parameterconfigured in a frame format, and configured to demodulate a signalgenerated based on the frame format, based on the radio parameter.

(9) Additionally, a terminal apparatus according to an aspect of thepresent invention is the terminal apparatus according to theabove-described (8) in which the signal demodulated by the receptionunit may be generated by selectively or simultaneously using a firstframe format having a different resource arrangement from a resourcearrangement of the frame format and a second frame format being theframe format.

(10) Additionally, a terminal apparatus according to an aspect of thepresent invention is the terminal apparatus according to theabove-described (9) in which the reception unit may perform blinddetection for whether the signal is generated based on the first frameformat or generated based on the second frame format.

(11) Additionally, a terminal apparatus according to an aspect of thepresent invention is the terminal apparatus according to theabove-described (10) in which a method of the blind detection may be asynchronization processing method performed by the reception unit or anacquiring method of a broadcast signal performed by the reception unit.

(12) Additionally, a communication method according to an aspect of thepresent invention is a communication method of a base station apparatusfor communicating with a terminal apparatus, the communication methodincludes the steps of: generating a transmit signal based on a frameformat in which a radio parameter is configurable; and notifying theterminal apparatus of information indicating the radio parameterconfigured in the frame format.

(13) Additionally, a communication method according to an aspect of thepresent invention is a communication method of a terminal apparatus forcommunicating with a base station apparatus, the communication methodincludes the steps of: acquiring information indicating a radioparameter configured in a frame format; and demodulating a signalgenerated based on the frame format, based on the radio parameter.

Effects of the Invention

According to an aspect of the present invention, a radio access networkcapable of being flexibly compatible with various requirements isprovided, and it is thus possible to efficiently provide a radiocommunication service to various use cases and usage scenarios withdifferent requirements.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating an example of a communication systemaccording to an aspect of the present invention.

FIG. 2 is a block diagram illustrating a configuration example of a basestation apparatus according to an aspect of the present invention.

FIG. 3 is a block diagram illustrating a configuration example of aterminal apparatus according to an aspect of the present invention.

FIG. 4 is a diagram illustrating an example of a frame format accordingto an aspect of the present invention.

FIG. 5 is a diagram illustrating an example of a frame format accordingto an aspect of the present invention.

FIG. 6 is a diagram illustrating an example of a frame format accordingto an aspect of the present invention.

FIGS. 7A to 7J are diagrams illustrating examples of a frame formataccording to an aspect of the present invention.

FIG. 8 is a diagram illustrating an example of a frame format accordingto an aspect of the present invention.

FIG. 9 is a diagram illustrating an example of a frame format accordingto an aspect of the present invention.

MODE FOR CARRYING OUT THE INVENTION

A communication system according to the present embodiment includes abase station apparatus (a transmission device, cells, a transmissionpoint, a group of transmit antennas, a group of transmit antenna ports,component carriers, eNodeB, an access point, an AP, a radio router, arepeater, a communication device) and terminal apparatuses (a terminal,a mobile terminal, a reception point, a reception terminal, a receptiondevice, a group of receive antennas, a group of receive antenna ports,UE, a station, an STA).

According to the present embodiment, “X/Y” includes the meaning of “X orY”. According to the present embodiment, “X/Y” includes the meaning of“X and Y”. According to the present embodiment, “X/Y” includes themeaning of “X and/or Y”.

1. First Embodiment

FIG. 1 is a diagram illustrating an example of a communication systemaccording to the present embodiment. As illustrated in FIG. 1, thecommunication system according to the present embodiment includes a basestation apparatus 1A and terminal apparatuses 2A and 2B. Coverage 1-1 isa range (a communication area) in which the base station apparatus 1Acan connect to the terminal apparatuses. Note that, the communicationsystem according to the present embodiment can include multiple basestation apparatuses and three or more terminal apparatuses.

With respect to FIG. 1, the following uplink physical channels are usedfor uplink radio communication from the terminal apparatuses 2 to thebase station apparatus 1A. The uplink physical channels are used fortransmission of information output from higher layers.

-   -   Physical Uplink Control CHannel (PUCCH)    -   Physical Uplink Shared CHannel (PUSCH)    -   Physical Random Access CHannel (PRACH)

The PUCCH is used for transmission of Uplink Control Information (UCI).The Uplink Control Information includes a positive ACKnowledgement (ACK)or a Negative ACKnowledgement (NACK) (ACK/NACK) for downlink data (adownlink transport block or a Downlink-Shared CHannel (DL-SCH)).ACK/NACK for the downlink data is also referred to as HARQ-ACK or HARQfeedback.

Here, the Uplink Control Information includes Channel State Information(CSI) for the downlink. The Uplink Control Information includes aScheduling Request (SR) used to request an Uplink-Shared CHannel(UL-SCH) resource. The Channel State Information refers to a RankIndicator RI specifying a suited spatial multiplexing number, aPrecoding Matrix Indicator PMI specifying a suited precoder, a ChannelQuality Indicator CQI specifying a suited transmission rate, and thelike.

The Channel Quality Indicator CQI (hereinafter, referred to as a CQIvalue) can be a suited modulation scheme (e.g., QPSK, 16QAM, 64QAM,256QAM, or the like) and a suited code rate in a predetermined band(details of which will be described later). The CQI value can be anindex (CQI Index) determined by the above change scheme, code rate, andthe like. The CQI value can take a value determined beforehand in thesystem.

The Rank Indicator and the Precoding Quality Indicator can take thevalues determined beforehand in the system. Each of the Rank Indicator,the Precoding Matrix Indicator, and the like can be an index determinedby the number of spatial multiplexing, Precoding Matrix information, orthe like. Note that values of the Rank Indicator, the Precoding MatrixIndicator, and the Channel Quality Indicator CQI are collectivelyreferred to as CSI values.

PUSCH is used for transmission of uplink data (an uplink transportblock, UL-SCH). Furthermore, PUSCH may be used for transmission ofACK/NACK and/or Channel State Information along with the uplink data. Inaddition, PUSCH may be used to transmit the Uplink Control Informationonly.

PUSCH is used to transmit an RRC message. The RRC message is asignal/information that is processed in a Radio Resource Control (RRC)layer. Further, PUSCH is used to transmit an MAC Control Element (CE).Here, MAC CE is a signal/information that is processed (transmitted) ina Medium Access Control (MAC) layer.

For example, a power headroom may be included in MAC CE and may bereported via PUSCH. In other words, a MAC CE field may be used toindicate a level of the power headroom.

The PRACH is used to transmit a random access preamble.

In the uplink radio communication, an UpLink Reference Signal (UL RS) isused as an uplink physical signal. The uplink physical signal is notused for transmission of information output from higher layers, but isused by the physical layer. The Uplink Reference Signal includes aDeModulation Reference Signal (DMRS) and a Sounding Reference Signal(SRS).

The DMRS is associated with transmission of the PUSCH or the PUCCH. Forexample, the base station apparatus 1A uses DMRS in order to performchannel compensation of PUSCH or PUCCH. The SRS is not associated withthe transmission of the PUSCH or the PUCCH. For example, the basestation apparatus 1A uses SRS to measure an uplink channel state. Thebase station apparatus 1A can report SRS configuration information withsignalling of a higher layer or a DCI format, which will be describedlater. The base station apparatus 1A can report DMRS configurationinformation with the signalling of the higher layer or the DCI format,which will be described later.

For the SRS, multiple ways of a trigger are defined. For example, atrigger type 0 in which the trigger is performed by the signalling ofthe higher layer and a trigger type 1 in which the trigger is performedby downlink control information, which will be described later, aredefined.

The SRS includes a Cell specific SRS (Common SRS) and a UE-specific SRS(Dedicated SRS). The UE-specific SRS includes the SRS that isperiodically transmitted (UR-specific periodic SRS) and the SRS that isaperiodically transmitted based on the trigger (UE-specific aperiodicSRS).

For the Common SRS, by the signalling of the higher layer or thedownlink control information, which will be described later, atransmission bandwidth (srs-BandwidthConfig) and a subframe fortransmission (srs-SubframeConfig) are specified. Additionally, in a casethat a prescribed parameter (for example,ackNackSRS-SimultaneousTransmission) is False, the Commmon SRS is nottransmitted by a subframe including the PUCCH including at least one ofthe HARQ-ACK and the SR. On the other hand, in a case that theprescribed parameter (for example, ackNackSRS-SimultaneousTransmission)is True, the Commmon SRS can be transmitted by the subframe includingthe PUCCH including at least one of the HARQ-ACK and the SR.

For the Dedicated SRS, by the signalling of the higher layer or thedownlink control information, which will be described later, atransmission bandwidth, a hopping bandwidth (srs-HoppingBandwidth), afrequency allocation start position (freqDomainPosition), a transmissionperiod (Duration) (Single transmission or indefinite transmission), atransmission cycle (srs-ConfigIndex), a cyclic shift amount provided toan SRS signal sequence (cyclicShift), an SRS position formed in acomb-teeth shape (transmissionComb) are configured.

The SRS can be transmitted from multiple antenna ports. The number ofthe transmit antenna ports are configured by the signalling of thehigher layer. The UE in which the SRS transmission in the multipleantenna ports is configured has to transmit the SRSs from all theconfigured transmit antenna ports to the serving cell by one SC-FDMAsymbol in the same subframe. In this case, for all the SRSs transmittedfrom the configured transmit antenna ports, the same transmissionbandwidth and frequency allocation start position are configured.

The UE in which multiple Transmission advance groups (TAGs) are notconfigured should not transmit the SRS unless the SRS and the PUSCHoverlap in the same symbol.

For a TDD serving cell, in a case that one SC-FDMA symbol is included inan UpPTS of the serving cell, the UE can use the SC-FDMA symbol for theSRS transmission. In a case that two SC-FDMA symbols are included in theUpPTS of the serving cell, the UE can use both the two SC-FDMA symbolsfor the SRS transmission. Additionally, in the SRS of the trigger type0, for the same UE, both the two SC-FDMA symbols can be configured forthe SRS.

In FIG. 1, the following downlink physical channels are used for thedownlink radio communication from the base station apparatus 1A to theterminal apparatus 2A. The downlink physical channels are used fortransmission of information output from higher layers.

-   -   Physical Broadcast CHannel (PBCH)    -   Physical Control Format Indicator CHannel (PCFICH)    -   Physical Hybrid automatic repeat request Indicator CHannel        (PHICH)    -   Physical Downlink Control CHannel (PDCCH)    -   Enhanced Physical Downlink Control CHannel (EPDCCH)    -   Physical Downlink Shared CHannel (PDSCH)

PBCH is used for broadcasting a Master Information Block (MIB, aBroadcast CHannel (BCH)) that is shared by the terminal apparatuses.PCFICH is used for transmission of information indicating a region(e.g., the number of OFDM symbols) to be used for transmission of PDCCH.

PHICH is used for transmission of ACK/NACK with respect to uplink data(a transport block, a codeword) received by the base station apparatus1A. In other words, PHICH is used for transmission of a HARQ indicator(HARQ feedback) indicating ACK/NACK with respect to the uplink data.Note that ACK/NACK is also called HARQ-ACK. The terminal apparatus 2Areports ACK/NACK having been received to a higher layer. ACK/NACK refersto ACK indicating a successful reception, NACK indicating anunsuccessful reception, and DTX indicating that no corresponding data ispresent. In a case that PHICH for uplink data is not present, theterminal apparatus 2A reports ACK to a higher layer.

The PDCCH and the EPDCCH are used for transmission of Downlink ControlInformation (DCI). Here, multiple DCI formats are defined fortransmission of the downlink control information. In other words, afield for the downlink control information is defined in a DCI formatand is mapped to information bits.

For example, as a DCI format for the downlink, DCI format 1A to be usedfor the scheduling of one PDSCH in one cell (transmission of a singledownlink transport block) is defined.

For example, the DCI format for the downlink includes downlink controlinformation such as information of PDSCH resource allocation,information of a Modulation and Coding Scheme (MCS) for the PDSCH, a TPCcommand for the PUCCH, and the like. Here, the DCI format for thedownlink is also referred to as downlink grant (or downlink assignment).

Furthermore, for example, as a DCI format for the uplink, DCI format 0to be used for the scheduling of one PUSCH in one cell (transmission ofa single uplink transport block) is defined.

For example, the DCI format for the uplink includes uplink controlinformation such as information of PUSCH resource allocation,information of the MCS for the PUSCH, a TPC command for the PUSCH, andthe like. Here, the DCI format for the uplink is also referred to asuplink grant (or uplink assignment).

Further, the DCI format for the uplink can be used to request (CSIrequest) downlink Channel State Information (CSI), which is also calledreception quality information. The Channel State Information refers tothe Rank Indicator (RI) specifying a suited number of spatialmultiplexing, the Precoding Matrix Indicator (PMI) specifying a suitedprecoder, the Channel Quality Indicator (CQI) specifying a suitedtransmission rate, Precoding Type Indicator (PTI) and the like.

The DCI format for the uplink can be used for a configuration indicatingan uplink resource to which a CSI feedback report is mapped, the CSIfeedback report being fed back to the base station apparatus by theterminal apparatus. For example, the CSI feedback report can be used fora configuration indicating an uplink resource for periodically reportingChannel State Information (periodic CSI). The CSI feedback report can beused for a mode configuration (CSI report mode) to periodically reportthe Channel State Information.

For example, the CSI feedback report can be used for a configurationindicating an uplink resource to report aperiodic Channel StateInformation (aperiodic CSI). The CSI feedback report can be used for amode configuration (CSI report mode) to aperiodically report the ChannelState Information. The base station apparatus can configure any one ofthe periodic CSI feedback report and the aperiodic CSI feedback report.In addition, the base station apparatus can configure both the periodicCSI feedback report and the aperiodic CSI feedback report.

The DCI format for the uplink can be used for a configuration indicatinga type of the CSI feedback report that is fed back to the base stationapparatus by the terminal apparatus. The type of the CSI feedback reportincludes wideband CSI (e.g., Wideband CQI), narrowband CSI (e.g.,Subband CQI), and the like.

In a case where a PDSCH resource is scheduled in accordance with thedownlink assignment, the terminal apparatus receives downlink data onthe scheduled PDSCH. In a case where a PUSCH resource is scheduled inaccordance with the uplink grant, the terminal apparatus transmitsuplink data and/or uplink control information on the scheduled PUSCH.

PDSCH is used for transmission of downlink data (a downlink transportblock, DL-SCH). PDSCH is used to transmit a system information blocktype 1 message. The system information block type 1 message iscell-specific information.

The PDSCH is used to transmit a system information message. The systeminformation message includes a system information block X other than thesystem information block type 1. The system information message iscell-specific information.

PDSCH is used to transmit an RRC message. Here, the RRC messagetransmitted from the base station apparatus may be shared by multipleterminal apparatuses in a cell. Further, the RRC message transmittedfrom the base station apparatus 1A may be a dedicated message to a giventerminal apparatus 2 (also referred to as dedicated signaling). In otherwords, user-equipment-specific information (unique to user equipment) istransmitted using a message dedicated to the given terminal apparatus.PDSCH is used for transmission of MAC CE.

Here, the RRC message and/or MAC CE is also referred to as higher layersignaling.

PDSCH can be used to request downlink channel state information. PDSCHcan be used for transmission of an uplink resource to which a CSIfeedback report is mapped, the CSI feedback report being fed back to thebase station apparatus by the terminal apparatus. For example, the CSIfeedback report can be used for a configuration indicating an uplinkresource for periodically reporting Channel State Information (periodicCSI). The CSI feedback report can be used for a mode configuration (CSIreport mode) to periodically report the Channel State Information.

The type of the downlink CSI feedback report includes wideband CSI(e.g., Wideband CSI) and narrowband CSI (e.g., Subband CSI). Thewideband CSI calculates one piece of Channel State Information for thesystem band of a cell. The narrowband CSI divides the system band inpredetermined units, and calculates one piece of Channel StateInformation for each division.

In the downlink radio communication, a Synchronization signal (SS) and aDownLink Reference Signal (DL RS) are used as downlink physical signals.The downlink physical signals are not used for transmission ofinformation output from the higher layers, but are used by the physicallayer.

The Synchronization signal is used for the terminal apparatus to besynchronized to frequency and time domains in the downlink. The DownlinkReference Signal is used for the terminal apparatus to perform channelcompensation on a downlink physical channel. For example, the DownlinkReference Signal is used for the terminal apparatus to calculate thedownlink Channel State Information.

Here, the Downlink Reference Signals include a Cell-specific ReferenceSignal (CRS), a UE-specific Reference Signal (URS) or aterminal-specific reference signal, a DeModulation Reference Signal(DMRS), a Non-Zero Power Chanel State Information-Reference Signal (NZPCSI-RS), and a Zero Power Chanel State Information-Reference Signal (ZPCSI-RS).

CRS is transmitted in all bands of a subframe and is used to performdemodulation of PBCH/PDCCH/PHICH/PCFICH/PDSCH. URS relating to PDSCH istransmitted in a subframe and a band that are used for transmission ofPDSCH to which URS relates, and is used to demodulate PDSCH to which URSrelates.

DMRS relating to EPDCCH is transmitted in a subframe and a band that areused for transmission of EPDCCH to which DMRS relates. DMRS is used todemodulate EPDCCH to which DMRS relates.

A resource for NZP CSI-RS is configured by the base station apparatus1A. The terminal apparatus 2A performs signal measurement (channelmeasurement), using NZP CSI-RS, for example. A resource for ZP CSI-RS isconfigured by the base station apparatus 1A. With zero output, the basestation apparatus 1A transmits ZP CSI-RS. The terminal apparatus 2Aperforms interference measurement in a resource to which NZP CSI-RScorresponds, for example.

A Multimedia Broadcast multicast service Single Frequency Network(MBSFN) RS is transmitted in all bands of the subframe used fortransmitting PMCH. MBSFN RS is used to demodulate PMCH. PMCH istransmitted on the antenna port used for transmission of MBSFN RS.

Here, the downlink physical channel and the downlink physical signal arealso collectively referred to as a downlink signal. The uplink physicalchannel and the uplink physical signal are also collectively referred toas an uplink signal. The downlink physical channels and the uplinkphysical channels are collectively referred to as physical channels. Thedownlink physical signals and the uplink physical signals are alsocollectively referred to as physical signals.

BCH, UL-SCH, and DL-SCH are transport channels. Channels used in theMedium Access Control (MAC) layer are referred to as transport channels.A unit of the transport channel used in the MAC layer is also referredto as a Transport Block (TB) or a MAC Protocol Data Unit (PDU). Thetransport block is a unit of data that the MAC layer delivers to thephysical layer. In the physical layer, the transport block is mapped toa codeword and subject to coding processing or the like on a codewordbasis.

Additionally, with respect to the terminal apparatus supporting CarrierAggregation (CA), the base station apparatus can integrate andcommunicate multiple Component Carriers (CC) for further broadbandtransmission. In the carrier aggregation, one Primary Cell (PCell) andone or multiple Secondary Cells (SCell) are configured as a set of theserving cells.

Additionally, in Dual Connectivity (DC), as a group of the servingcells, a Master Cell Group (MCG) and a Secondary Cell Group (SCG) areconfigured. The MCG is configured of the PCell and optional one ormultiple SCells. Additionally, the SCG is configured of a primary SCell(PSCell) and optional one or multiple SCells.

FIG. 2 is a schematic block diagram illustrating a configuration of thebase station apparatus 1A according to the present embodiment. Asillustrated in FIG. 2, the base station apparatus 1A is configured,including a higher layer processing unit (higher layer processing step)101, a control unit (controlling step) 102, a transmission unit(transmitting step) 103, a reception unit (receiving step) 104, and anantenna 105. The higher layer processing unit 101 is configured,including a radio resource control unit (radio resource controllingstep) 1011 and a scheduling unit (scheduling step) 1012. Thetransmission unit 103 is configured, including a coding unit (codingstep) 1031, a modulation unit (modulating step) 1032, a frameconfiguration unit (frame configuring step) 1033, a multiplexing unit(multiplexing step) 1034, and a radio transmission unit (radiotransmitting step) 1035. The reception unit 104 is configured, includinga radio reception unit (radio receiving step) 1041, a demultiplexingunit (demultiplexing step) 1042, a demodulation unit (demodulating step)1043, and a decoding unit (decoding step) 1044.

The higher layer processing unit 101 performs processing of the MediumAccess Control (MAC) layer, the Packet Data Convergence Protocol (PDCP)layer, the Radio Link Control (RLC) layer, and the Radio ResourceControl (RRC) layer. Furthermore, the higher layer processing unit 101generates information necessary for control of the transmission unit 103and the reception unit 104, and outputs the generated information to thecontrol unit 102.

The higher layer processing unit 101 receives information of a terminalapparatus, such as UE capability, capability information, or the like,from the terminal apparatus. To rephrase, the terminal apparatustransmits its function to the base station apparatus by higher layersignaling.

Note that in the following description, information of a terminalapparatus includes information indicating whether the stated terminalapparatus supports a prescribed function, or information indicating thatthe stated terminal apparatus has completed the introduction and test ofa prescribed function. In the following description, information ofwhether the prescribed function is supported includes information ofwhether the introduction and test of the prescribed function have beencompleted.

For example, in a case where a terminal apparatus supports a prescribedfunction, the stated terminal apparatus transmits information(parameters) indicating whether the prescribed function is supported. Ina case where a terminal apparatus does not support a prescribedfunction, the stated terminal apparatus does not transmit information(parameters) indicating whether the prescribed function is supported. Inother words, whether the prescribed function is supported is reported bywhether information (parameters) indicating whether the prescribedfunction is supported is transmitted. Information (parameters)indicating whether a prescribed function is supported may be reportedusing one bit of 1 or 0.

The radio resource control unit 1011 generates, or acquires from ahigher node, the downlink data (the transport block) arranged in thedownlink PDSCH, system information, the RRC message, the MAC ControlElement (CE), and the like. The radio resource control unit 1011 outputsthe downlink data to the transmission unit 103, and outputs otherinformation to the control unit 102. Furthermore, the radio resourcecontrol unit 1011 manages various configuration information of theterminal apparatuses.

The scheduling unit 1012 determines a frequency and a subframe to whichthe physical channels (PDSCH and PUSCH) are allocated, the code rate andmodulation scheme (or MCS) for the physical channels (PDSCH and PUSCH),the transmit power, and the like. The scheduling unit 1012 outputs thedetermined information to the control unit 102.

The scheduling unit 1012 generates the information to be used for thescheduling of the physical channels (PDSCH and PUSCH), based on theresult of the scheduling. The scheduling unit 1012 outputs the generatedinformation to the control unit 102.

Based on the information input from the higher layer processing unit101, the control unit 102 generates a control signal for controlling ofthe transmission unit 103 and the reception unit 104. The control unit102 generates the downlink control information based on the informationinput from the higher layer processing unit 101, and outputs thegenerated information to the transmission unit 103.

The transmission unit 103 generates the downlink reference signal inaccordance with the control signal input from the control unit 102,codes and modulates the HARQ indicator, the downlink controlinformation, and the downlink data that are input from the higher layerprocessing unit 101, multiplexes the PHICH, the PDCCH, the EPDCCH, thePDSCH, and the downlink reference signal, and transmits a signalobtained through the multiplexing to the terminal apparatus 2 throughthe antenna 105.

The coding unit 1031 codes the HARQ indicator, the downlink controlinformation, and the downlink data that are input from the higher layerprocessing unit 101, in compliance with the coding scheme prescribed inadvance, such as block coding, convolutional coding, or turbo coding, orin compliance with the coding scheme determined by the radio resourcecontrol unit 1011. The modulation unit 1032 modulates the coded bitsinput from the coding unit 1031, in compliance with the modulationscheme prescribed in advance, such as Binary Phase Shift Keying (BPSK),Quadrature Phase Shift Keying (QPSK), quadrature amplitude modulation(16QAM), 64QAM, or 256QAM, or in compliance with the modulation schemedetermined by the radio resource control unit 2011.

The multiplexing unit 1034 multiplexes the modulated modulation symbolof each channel, the generated downlink reference signal, and thedownlink control information. To be more specific, the multiplexing unit1034 maps the modulated modulation symbol of each channel, the generateddownlink reference signal, and the downlink control information to theresource elements. Note that, the downlink reference signal is generatedby the transmission unit 103 based on a sequence that is already knownto the terminal apparatus 2A and that is acquired in accordance with arule prescribed in advance based on the physical cell identity (PCI,cell ID) for identifying the base station apparatus 1A, and the like.

The frame configuration unit 1033 provides a frame configuration (frameformat, frame constitution, frame structure) of a transmit signalgenerated by the transmission unit 103. The operation of the frameconfiguration unit 1033 will be described later. Note that, although thefollowing descriptions assume that the transmission unit 103 includesthe frame configuration unit 1033, other configuration units may includethe function of the frame configuration unit 1033, which will bedescribed later. For example, the higher layer processing unit 101 mayinclude the function.

The radio transmission unit 1035 performs Inverse Fast Fourier Transform(IFFT) on the modulation symbol resulting from the multiplexing or thelike, generates an OFDM symbol, attaches a Cyclic Prefix (CP) to thegenerated OFDM symbol, generates a baseband digital signal, converts thebaseband digital signal into an analog signal, removes unnecessaryfrequency components through filtering, up-converts a result of theremoval into a signal of a carrier frequency, performs poweramplification, and outputs a final result to the antenna 105 fortransmission.

In accordance with the control signal input from the control unit 102,the reception unit 104 demultiplexes, demodulates, and decodes thereception signal received from the terminal apparatus 2A through thetransmit and/or receive antenna 105, and outputs information resultingfrom the decoding to the higher layer processing unit 101.

In accordance with the control signal input from the control unit 102,the reception unit 104 demultiplexes, demodulates, and decodes thereception signal received from the terminal apparatus 2A through theantenna 105, and outputs information resulting from the decoding to thehigher layer processing unit 101.

The radio reception unit 1041 converts, by down-converting, an uplinksignal received through the transmit and/or receive antenna 105 into abaseband signal, removes unnecessary frequency components, controls theamplification level in such a manner as to suitably maintain a signallevel, performs orthogonal demodulation based on an in-phase componentand an orthogonal component of the received signal, and converts theresulting orthogonally-demodulated analog signal into a digital signal.

The radio reception unit 1041 removes a portion corresponding to CP fromthe digital signal resulting from the conversion. The radio receptionunit 1041 performs Fast Fourier Transform (FFT) on the signal from whichCP has been removed, extracts a signal in the frequency domain, andoutputs the resulting signal to the demultiplexing unit 1042.

The demultiplexing unit 1042 demultiplexes the signal input from theradio reception unit 1041 into PUCCH, PUSCH, and the signal such as theuplink reference signal. The demultiplexing is performed based on radioresource allocation information that is determined in advance by thebase station apparatus 1A using the radio resource control unit 1011 andthat is included in the uplink grant notified to each of the terminalapparatuses 2.

Furthermore, the demultiplexing unit 1042 makes a compensation ofchannels including PUCCH and PUSCH. The demultiplexing unit 1042demultiplexes the uplink reference signal.

The demodulation unit 1043 performs Inverse Discrete Fourier Transform(IDFT) on PUSCH, acquires modulation symbols, and performs receptionsignal demodulation, that is, demodulates each of the modulation symbolsof PUCCH and PUSCH, in compliance with the modulation scheme prescribedin advance, such as BPSK, QPSK, 16QAM, 64QAM, 256QAM, or the like, or incompliance with the modulation scheme that the base station apparatus 1Aitself notified in advance, with the uplink grant, each of the terminalapparatuses 2.

The decoding unit 1044 decodes the coded bits of PUCCH and PUSCH, whichhave been demodulated, at the code rate in compliance with a codingscheme prescribed in advance, the code rate being prescribed in advanceor being notified in advance with the uplink grant to the terminalapparatus 2 by the base station apparatus 1A itself, and outputs thedecoded uplink data and uplink control information to the higher layerprocessing unit 101. In a case that PUSCH is re-transmitted, thedecoding unit 1044 performs the decoding with the coded bits input fromthe higher layer processing unit 101 and retained in an HARQ buffer, andthe demodulated coded bits.

FIG. 3 is a schematic block diagram illustrating a configuration of theterminal apparatus 2 (terminal apparatus 2A and terminal apparatus 2B)according to the present embodiment. As illustrated in FIG. 3, theterminal apparatus 2A is configured, including a higher layer processingunit (higher layer processing step) 201, a control unit (controllingstep) 202, a transmission unit (transmitting step) 203, a reception unit(receiving step) 204, a channel state information generating unit(channel state information generating step) 205, and an antenna 206. Thehigher layer processing unit 201 is configured, including a radioresource control unit (radio resource controlling stop) 2011 and ascheduling information interpretation unit (scheduling informationinterpreting step) 2012. The transmission unit 203 is configured,including a coding unit (coding step) 2031, a modulation unit(modulating step) 2032, a frame configuration unit (frame configuringstep) 2033, a multiplexing unit (multiplexing step) 2034, and a radiotransmission unit (radio transmitting step) 2035. The reception unit 204is configured, including a radio reception unit (radio receiving step)2041, a demultiplexing unit (demultiplexing step) 2042, and a signaldetection unit (signal detecting step) 2043.

The higher layer processing unit 201 outputs the uplink data (thetransport block) generated by a user operation or the like, to thetransmission unit 203. The higher layer processing unit 201 performsprocessing of the Medium Access Control (MAC) layer, the Packet DataConvergence Protocol (PDCP) layer, the Radio Link Control (RLC) layer,and the Radio Resource Control (RRC) layer.

The higher layer processing unit 201 outputs, to the transmission unit203, information indicating a terminal apparatus function supported bythe terminal apparatus 2A itself.

Furthermore, the radio resource control unit 2011 manages variousconfiguration information of the terminal apparatuses 2A itself.Furthermore, the radio resource control unit 2011 generates informationto be mapped to each uplink channel, and outputs the generatedinformation to the transmission unit 203.

The radio resource control unit 2011 acquires configuration informationof CSI feedback transmitted from the base station apparatus, and outputsthe acquired information to the control unit 202.

The scheduling information interpretation unit 2012 interprets thedownlink control information received through the reception unit 204,and determines scheduling information. The scheduling informationinterpretation unit 2012 generates the control information in order tocontrol the reception unit 204 and the transmission unit 203 inaccordance with the scheduling information, and outputs the generatedinformation to the control unit 202.

Based on the information input from the higher layer processing unit201, the control unit 202 generates a control signal for controlling thereception unit 204, the channel state information generating unit 205,and the transmission unit 203. The control unit 202 outputs thegenerated control signal to the reception unit 204, the channel stateinformation generating unit 205, and the transmission unit 203 tocontrol the reception unit 204 and the transmission unit 203.

The control unit 202 controls the transmission unit 203 to transmit CSIgenerated by the channel state information generating unit 205 to thebase station apparatus.

In accordance with the control signal input from the control unit 202,the reception unit 204 demultiplexes, demodulates, and decodes areception signal received from the base station apparatus 1A through theantenna 206, and outputs the decoded information to the higher layerprocessing unit 201.

The radio reception unit 2041 converts, by down-converting, a downlinksignal received through the antenna 206 into a baseband signal, removesunnecessary frequency components, controls an amplification level insuch a manner as to suitably maintain a signal level, performsorthogonal demodulation based on an in-phase component and an orthogonalcomponent of the received signal, and converts the resultingorthogonally-demodulated analog signal into a digital signal.

The radio reception unit 2041 removes a portion corresponding to CP fromthe digital signal resulting from the conversion, performs fast Fouriertransform on the signal from which CP has been removed, and extracts asignal in the frequency domain.

The demultiplexing unit 2042 demultiplexes the extracted signal intoPHICH, PDCCH, EPDCCH, PDSCH, and the downlink reference signal. Further,the demultiplexing unit 2042 makes a compensation of channels includingPHICH, PDCCH, and EPDCCH based on a channel estimation value of thedesired signal obtained from the channel measurement, detects thedownlink control information, and outputs the information to the controlunit 202. The control unit 202 outputs PDSCH and the channel estimationvalue of the desired signal to the signal detection unit 2043.

The signal detection unit 2043, using PDSCH and the channel estimationvalue, detects a signal, and outputs the detected signal to the higherlayer processing unit 201.

The transmission unit 203 generates the uplink reference signal inaccordance with the control signal input from the control unit 202,codes and modulates the uplink data (the transport block) input from thehigher layer processing unit 201, multiplexes the PUCCH, the PUSCH, andthe generated uplink reference signal, and transmits a result of themultiplexing to the base station apparatus 1A through the antenna 206.

The coding unit 2031 codes the uplink control information input from thehigher layer processing unit 201 in compliance with a coding scheme,such as convolutional coding or block coding. Furthermore, the codingunit 2031 performs turbo coding in accordance with information used forthe scheduling of PUSCH.

The modulation unit 2032 modulates coded bits input from the coding unit2031, in compliance with the modulation scheme notified with thedownlink control information, such as BPSK, QPSK, 16QAM, or 64QAM, or incompliance with a modulation scheme prescribed in advance for eachchannel.

In accordance with the control signal input from the control unit 202,the multiplexing unit 2034 rearranges modulation symbols of PUSCH inparallel and then performs Discrete Fourier Transform (DFT) on therearranged modulation symbols. Furthermore, the multiplexing unit 2034multiplexes PUCCH and PUSCH signals and the generated uplink referencesignal for each transmit antenna port. To be more specific, themultiplexing unit 2034 maps the PUCCH and PUSCH signals and thegenerated uplink reference signal to the resource elements for eachtransmit antenna port. Note that the uplink reference signal isgenerated by the transmission unit 203 based on a sequence acquiredaccording to a rule (formula) prescribed in advance, based on a physicalcell identity (PCI, also referred to as a cell ID or the like) foridentifying the base station apparatus 1A, a bandwidth to which theuplink reference signal is mapped, a cyclic shift notified with theuplink grant, a parameter value for generation of a DMRS sequence, andthe like.

The frame configuration unit 2033 provides the frame format of thetransmit signal generated by the transmission unit 203 (frame structure,frame type, frame form, frame pattern, frame generation method, framedefinition), information indicating the frame format, or the frameitself in the same manner as the frame configuration unit 1033 includedin the base station apparatus 1A. The operation of the frameconfiguration unit 2033 will be described later. Note that, it goeswithout saying that the function of the frame configuration unit 2033may be included in other configuration units (for example, the higherlayer processing unit 201).

The radio transmission unit 2035 performs Inverse Fast Fourier Transform(IFFT) on a signal resulting from the multiplexing, performs themodulation of SC-FDMA scheme, generates an SC-FDMA symbol, attaches CPto the generated SC-FDMA symbol, generates a baseband digital signal,converts the baseband digital signal into an analog signal, removesunnecessary frequency components, up-converts a result of the removalinto a signal of a carrier frequency, performs power amplification, andoutputs a final result to the transmit and/or receive antenna 206 fortransmission.

The signal detection unit 2043 according to the present embodiment canperform demodulation processing based on information relating to amultiplexing state of a transmit signal addressed to the terminalapparatus itself and information relating to a re-transmission state ofthe transmit signal addressed to the terminal apparatus itself.

FIG. 4 is a schematic diagram illustrating an example of the frameformat (first frame format, first frame structure) of the downlinksignal generated by the frame configuration unit 1033 according to thepresent embodiment. As illustrated in FIG. 4, the first frame formatincludes at least any one of a control signal resource 4000, a datasignal resource 4001, a common reference signal (common RS,cell-specific RS) resource 4002, a specific reference signal (specificRS, demodulation reference signal, demodulation RS, terminal-specificreference signal) resource 4003.

A signal waveform (transmission scheme) achieving the frame is notlimited to any specific one, may be a multi-carrier transmission schemerepresented by OFDM transmission, or a single-carrier transmissionscheme represented by SC-FDMA transmission. For example, in a case ofthe OFDM transmission, the first frame format is configured of multipleOFDM signals.

A time length (time cycle) and a bandwidth of each of the resources arenot limited to any specific one. For example, the control signalresource 4000 can include three OFDM symbol lengths as the time length,and include 12 subcarriers as the bandwidth.

In the first frame format, aggregation in a time domain and a frequencydomain can be performed. FIG. 5 is a schematic diagram illustrating anexample of the frame format of the downlink signal generated by theframe configuration unit 1033 according to the present embodiment. Inthe example of FIG. 5, by N pieces of subframes 5000 being aggregated inthe time domain, one frame is configured. The subframe 5000 can have theconfiguration of the first frame format illustrated in FIG. 4. Notethat, according to the example of FIG. 5, although a frequency bandwidthoccupied by the frame is the same as a frequency bandwidth of thesubframe 5000, the frame can be configured by the subframes 5000 beingaggregated in the frequency domain. For example, in a case of aconfiguration in which eight pieces of the subframes 5000 are arrangedin the frequency domain, a frequency bandwidth occupied by the framebecomes eight times the frequency bandwidth of the subframe 5000. Asillustrated in FIG. 5, in a case that the frame is configured ofmultiple subframes, the frame format illustrated in FIG. 4 is alsoreferred to as a first subframe format, and the frame format illustratedin FIG. 5 is also referred to as a first frame format.

Note that, in the present embodiment, although binding multiplesubframes to form one frame is referred to as aggregation, the frameconfiguration unit 1033 can define a frame format generated by arrangingmultiple subframes in the time domain and the frequency domain as oneframe format from the beginning. Additionally, the number of bundles inthe time domain and/or the frequency domain may be configured as aparameter. In this case, this parameter is indicated from the basestation apparatus to the terminal apparatus.

Returning to FIG. 4, the control signal resource 4000 includes controlinformation relating to a downlink signal transmitted by the basestation apparatus 1A. The control information is, for example,information transmitted on the PDCCH by the base station apparatus 1A.The control information includes common control information broadcast toall the terminal apparatuses connected to the base station apparatus 1Aand specific control information individually reported to each of theterminal apparatuses connected to the base station apparatus 1A.

The data signal resource 4001 includes a data signal transmitted by thebase station apparatus 1A. The data signal is, for example, informationtransmitted on the PDSCH by the base station apparatus 1A.

In the common RS resource 4002, a common reference signal (common RS,cell-specific reference signal) that is transmitted to all the terminalapparatuses connected to the base station apparatus 1A is mapped. Thecommon RS is used by the terminal apparatus 2A to estimate informationrelated to a reception quality of the terminal apparatus itself (forexample, the CSI). Additionally, the common RS is also used by theterminal apparatus 2A to demodulate a signal transmitted by the controlsignal resource 4000. Additionally, the common RS is also used by theterminal apparatus 2A to detect the base station apparatus 1A.Additionally, the common RS is also used by the terminal apparatus 2A toperform synchronization processing (sampling synchronization, FFTsynchronization) to a signal transmitted from the base station apparatus1A.

In the specific RS resource 4003, a specific reference signal (specificRS, demodulation reference signal) that is individually transmitted toeach of the terminal apparatuses 2 connected to the base stationapparatus 1A is mapped. The specific RS is related to the data signalthat is mapped in the data signal resource 4001 by the base stationapparatus 1A and addressed to each of the terminal apparatuses. Theterminal apparatus 2A can use the specific RS transmitted to theterminal apparatus itself in order to demodulate the data signal mappedin the data signal resource 4001 and addressed to the terminal apparatusitself.

As illustrated in FIG. 4, in the first frame format, the data signalresource 4001 can include the common RS resource 4002 and the specificRS resource 4003. Additionally, the frame configuration unit 1033 canarrange the common RS resource 4002 and the specific RS resource 4003 ina non-contiguous manner in the time domain and the frequency domain.Note that, the frame configuration unit 1033 may further include acontrol information resource 4000 in the data signal resource 4001. Thecontrol information resource 4000 included in the data signal resource4001 by the frame configuration unit 1033 is, for example, a resource inwhich the EPDCCH is arranged. The resource may be time-multiplexed orfrequency-multiplexed to a resource in which another signal is mapped inthe data signal resource 4001.

The frame configuration unit 1033 can further include a synchronizationsignal resource 4004 and a broadcast signal resource 4007 in the firstframe format. In the synchronization signal resource 4004 and thebroadcast signal resource 4007, a synchronization signal and a broadcastsignal that are broadcast to the terminal apparatus 2 capable ofreceiving the signal transmitted from the base station apparatus 1A aremapped. The synchronization signal is a signal for the terminalapparatus 2A to perform an initial synchronization with respect to thesignal transmitted from the base station apparatus 1A, and is a PrimarySynchronization Signal (PSS) or a Secondary Synchronization Signal(SSS), for example. The broadcast signal is a signal for the terminalapparatus 2A to acquire system information relating to the base stationapparatus 1A, and includes, for example, information transmitted on thePBCH by the base station apparatus 1A. The frame configuration unit 1033may not necessarily arrange the synchronization signal resource 4004 andthe broadcast signal resource 4007 for all the subframes.

The base station apparatus 1A can report (indicate) resource positionswhere the synchronization signal resource 4004 and the broadcast signalresource 4007 are arranged (or resource candidates having arrangementpossibility) to the terminal apparatus 2A. Additionally, the basestation apparatus 1A and the terminal apparatus 2A can determinebeforehand the resource positions where the synchronization signalresource 4004 and the broadcast signal resource 4007 are arranged (orthe resource candidates having the arrangement possibility). Note that,here, the information indicating the resource position includesinformation indicating a time resource (subframe number, OFDM signalnumber, frame number, slot number, or the like), a frequency resource(subcarrier number, resource block number, frequency band number, or thelike), a space resource (transmit antenna number, antenna port number,space stream number, or the like), a code resource (spread codesequence, code generation formula, code generation seed, or the like),or the like.

Note that, hereinafter, in the same manner as the above description, acase of a description that is “the base station apparatus 1A notifiesthe terminal apparatus 2A of information” also includes, unlessotherwise noted, a state in which the information is shared beforehandbetween the base station apparatus 1A and the terminal apparatus 2A (ora state in which the information is determined beforehand). In general,by the base station apparatus 1A notifying the terminal apparatus 2A ofthe information, although overhead increases, it is possible to becompatible with a radio propagation environment that changes everymoment. On the other hand, by the base station apparatus 1A and theterminal apparatus 2A sharing the information beforehand, although itmay be difficult in some cases to be compatible with the radiopropagation environment that changes every moment, the overhead reduces.

FIG. 6 is a schematic diagram illustrating an example of the frameformat (second frame format, second frame structure) of the downlinksignal generated by the frame configuration unit 1033 according to thepresent embodiment. As illustrated in FIG. 6, the second frame formatincludes at least any one of the control signal resource 4000, the datasignal resource 4001, the common RS resource 4002, and the specific RSresource 4003.

In the second frame format, the common RS resource 4002 and the datasignal resource 4001 are temporally and sequentially arranged.Additionally, in the second frame format, the common RS resource 4002and the control signal resource 4000 are arranged in the first half ofthe frame. Note that, in the example illustrated in FIG. 6, although thespecific RS resource 4003 is also arranged in the first half of theframe, the frame configuration unit 1033 can include the specific RSresource 4003 in the data signal resource 4001. In a case that the datasignal resource 4001 includes the specific RS resource 4003, the frameconfiguration unit 1033 can arrange the specific RS resource 4003 in arange of the data signal resource 4001 in a non-contiguous manner in thetime domain and the frequency domain.

Note that, the frame configuration unit 1033 may further include thecontrol information resource 4000 in the data signal resource 4001. Asignal mapped in the control information resource 4000 included in thedata signal resource 4001 by the frame configuration unit 1033 is, forexample, a signal transmitted on the EPDCCH. The control informationresource 4000 may be time-multiplexed or frequency-multiplexed to aresource in which another signal is mapped in the data signal resource4001.

The terminal apparatus 2A that receives a transmit signal generatedbased on the second frame format can perform initial synchronizationprocessing on the apparatus that transmits the transmit signal by usingthe common RS mapped in the common RS resource 4002 arranged in thefirst half of the frame. In other words, the frame configuration unit1033 according to the present embodiment can include the synchronizationsignal resource 4004 in the common RS resource 4002 in the second frameformat. The frame configuration unit 1033 can arrange the common RSresource 4002 and the synchronization signal resource 4004 in a commonresource in the second frame format. The frame configuration unit 1033can make a part of the common RS mapped in the common RS resource 4002 asynchronization signal.

The frame configuration unit 1033 can arrange the synchronization signalresource 4004 in the first frame format and the synchronization signalin the second frame format in a common resource, or different resources.The base station apparatus 1A can make the synchronization signaltransmitted by the synchronization signal resource 4004 arranged in thefirst frame format and the synchronization signal transmitted by thesynchronization signal resource 4004 arranged in the second frame formatthe same signal, or can make them different signals. Here, the samesignal includes that information included in the signal or a radioparameter applied to the signal is at least partially common.

In a case that the resources where the frame configuration unit 1033arranges the synchronization signal resource 4004 (or the broadcastsignal resource 4007) in the first frame format and the second frameformat are different, the reception unit 204 of the terminal apparatus2A can perform synchronization processing on the multiple resourceshaving arrangement possibility of the synchronization signal resource4004. Additionally, the reception unit 204 of the terminal apparatus 2Acan recognize the frame format of the signal received by the terminalapparatus itself based on a result of the synchronization processing onthe multiple resources. For example, in a case that the reception unit204 of the terminal apparatus 2A performs the synchronization processingon the resources having the arrangement possibility of thesynchronization signal resource 4004 in the second frame format anddetermines that the resources are synchronized as the result, thereception unit 204 of the terminal apparatus 2A can recognize that theframe format of the signal received by the terminal apparatus itself isthe second frame format. In other words, the terminal apparatus 2A canblindly detect the frame format. According to the method describedabove, the terminal apparatus 2A can blindly detect the frame format bythe synchronization processing.

The frame configuration unit 1033 can further include the broadcastsignal resource 4007 in the second frame format. In the same manner asthe first frame format, the frame configuration unit 1033 need notinclude the broadcast signal resource 4007 in all the transmit signal.The resource where the broadcast signal resource 4007 is arranged in thesecond frame format by the frame configuration unit 1033 can be the sameas or different from the resource where the broadcast signal resource4007 is arranged in the first frame format by the frame configurationunit 1033.

The base station apparatus 1A and the terminal apparatus 2A candetermine beforehand resources where the synchronization signal resource4004 and the broadcast signal resource 4007 are arranged (or resourcecandidates having arrangement possibility) for each of the frameformats. In this case, by the base station apparatus 1A notifying theterminal apparatus 2A of the frame format of the signal transmitted bythe base station apparatus itself, the base station apparatus 1A cannotify the terminal apparatus 2A of the resource or the resourcecandidate group.

Additionally, the base station apparatus 1A can make informationincluded in the signal transmitted by the broadcast signal resource 4007arranged in the first frame format and information included in thesignal transmitted by the broadcast signal resource 4007 arranged in thesecond frame format common information, or different pieces ofinformation. Additionally, the base station apparatus 1A can make aradio parameter (code rate, modulation scheme, code length, spread rate,or the like) of the signal transmitted by the broadcast signal resource4007 arranged in the first frame format and a radio parameter of thesignal transmitted by the broadcast signal resource 4007 arranged in thesecond frame format a common radio parameter, or different radioparameters.

The base station apparatus 1A can notify the terminal apparatus 2A of aresource where the frame configuration unit 1033 arranges the broadcastsignal resource 4007 in the second frame format (or resource candidatehaving the arrangement possibility). The base station apparatus 1A cannotify the terminal apparatus 2A of a resource where the broadcastsignal resource 4007 is arranged in the first frame format and aresource where the broadcast signal resource 4007 is arranged in thesecond frame format individually.

Note that, it goes without saying that the information relating to eachof the resources reported to the terminal apparatus 2A by the basestation apparatus 1A can be determined beforehand between the basestation apparatus 1A and the terminal apparatus 2A.

The terminal apparatus 2A connected to the base station apparatus 1A canrecognize the frame format of the signal received by the terminalapparatus itself by acquiring information included in the signaltransmitted by the broadcast signal resource 4007. Additionally, in acase that the frame configuration unit 1033 of the base stationapparatus 1A changes the resource where the broadcast signal resource4007 is arranged in accordance with the frame format, the reception unit204 of the terminal apparatus 2A can perform demodulation processing ofthe broadcast signal on the resource having the arrangement possibilityof the broadcast signal resource 4007. The terminal apparatus 2A canrecognize the frame format of the signal received by the terminalapparatus itself based on information indicating the resource where thebroadcast signal that can be correctly demodulated is mapped. In otherwords, the terminal apparatus 2A can blindly detect the frame format.According to the method described above, the terminal apparatus 2A canblindly detect the frame format by acquiring the broadcast signal.

The frame configuration unit 1033 can define the second frame format byusing the frame format illustrated in FIG. 6 as a second subframe format(second subframe) and aggregating the subframes in the time domain andthe frequency domain in the same manner as the first frame format. Atthe aggregation of the subframes, the frame configuration unit 1033 canaggregate frames including all the common RS resource 4001, the controlinformation resource 4000, the data signal resource 4001, and thespecific RS resource 4003, and can aggregate frames including resourcesof a specific combination among the above-described four resources. Forexample, at the aggregation of the frames, the frame configuration unit1033 can aggregate only the multiple data signal resources 4001.

FIGS. 7A to 7J are schematic diagrams illustrating examples of the frameformat (second frame format) of the downlink signal generated by theframe configuration unit 1033 according to the present embodiment. FIG.7A illustrates a case that the aggregation is not performed. Asillustrated in FIG. 7B, the frame configuration unit 1033 can aggregatethe data signal resources 4001 in the time domain. According to theexample in FIG. 7B, the base station apparatus 1A can flexibly changethe frame format in accordance with a data size (payload size) addressedto the terminal apparatus 2A.

As illustrated in FIG. 7C, the frame configuration unit 1033 can alsoaggregate the specific RS resources 4003 in the time domain in additionto the data signal resources 4001. According to FIG. 7C, the basestation apparatus 1A can map data signals addressed to differentterminal apparatuses 2 to the data signal resources 4001, respectively.Additionally, the specific RS is periodically mapped in the time domain,the base station apparatus 1A can therefore provide stable radiocommunication even to the terminal apparatus 2 under a high speed mobileenvironment.

As illustrated in FIG. 7D, the frame configuration unit 1033 canaggregate the data signal resources 4001 in the time domain, and canmatch a frame length of each of the data signal resources 4001 to beaggregated with a frame length without the aggregation (a frame lengthof the frame illustrated in FIG. 7A). According to FIG. 7D, even in acase that the base station apparatuses positioned in the vicinitytransmit the downlink signals, with different aggregation sizes fromeach other, based on the second frame format, it is possible tosynchronize frames between the base station apparatuses with ease. Asillustrated in FIG. 7E, in a case that the specific RS resources 4003are aggregated in the time domain in addition to the data resourcesignal resource 4001 as well, the frame lengths of the frames to beaggregated can of course be made uniform.

As illustrated in FIG. 7F, the frame configuration unit 1033 can furtheraggregate the common RS resources 4002 and the control signal resources4000 in the time domain. Additionally, as illustrated in FIG. 7G andFIG. 7H, the frame configuration unit 1033 can include anon-transmission section (NULL section) of the base station apparatus 1Ain the frame format. The length of the non-transmission section may bethe same as the length of the data signal resource 4001, or may be anintegral multiple of a length of an element constituting the data signalresource 4001 (for example, OFDM signal length).

As illustrated in FIG. 71, the frame configuration unit 1033 canaggregate the control information resources 4000, the common RSresources 4002 and the specific RS resources 4003. By the frameconfiguration unit 1033 aggregating the common RS resources 4002, thetransmission unit 103 can apply different beamforming for the common RSsthat are transmitted by the common RS resources, respectively.Accordingly, for example, the terminal apparatus 2A can notify theconnected base station apparatus 1A of a reception quality associatedwith the multiple common RSs.

As illustrated in FIG. 7J, the frame configuration unit 1033 can use thesecond frame format that does not include the control informationresource 4000, and can also use the second frame format that does notinclude the control information resource 4000 and the common RS resource4002.

As illustrated in FIG. 7J, in a case that the base station apparatus 1Atransmits a signal based on the second frame format that does notinclude the control information resource 4000 or the common RS resource4002, the base station apparatus 1A can transmit the second frame formatthat includes the control information resource 4000 or the common RSresource 4002 at another frequency. For example, the base stationapparatus 1A transmits, for a signal transmitted in a high frequencyband of 6 GHz or higher, the signal based on the second frame formatthat does not include the control information resource 4000 or thecommon RS resource 4002, whereas the base station apparatus 1A cantransmit, for a signal transmitted in a low frequency band of lower than6 GHz, the signal based on the second frame format that includes thecontrol information resource 4000 or the common RS resource 4002. Inthis case, the base station apparatus 1A can transmit, for a signaltransmitted in the low frequency band of lower than 6 GHz, the signalbased on the second frame format that does not include the specific RSresource 4003 or the data signal resource 4001.

Note that, in a case that the frame configuration unit 1033 aggregatesthe signals generated based on the second frame format in the timedomain and the frequency domain, the number of the resources in each ofthe resource types included in each of the signals to be aggregated (forexample, the common RS resource 4001 or the data signal resource 4002)may be the same, or may be different from each other. Note that,however, from the standpoint of suppressing overhead relating tosignalling from the base station apparatus 1A to the terminal apparatus2A, the number of the resources is preferably associated with the signallengths and the frequency bandwidths of the signals to be aggregated.Additionally, the frame lengths or the frequency bandwidths of themultiple frames to be aggregated may be a common value, or may bedifferent values. Note that, however, from the standpoint of suppressingoverhead relating to signalling from the base station apparatus 1A tothe terminal apparatus 2A, a relationship between the frames in theframe lengths and the frequency bandwidths is preferably a relationshipof an integral multiple.

FIG. 8 is a schematic diagram illustrating a configuration example of aframe format according to the present embodiment. As illustrated in FIG.8, the frame configuration unit 1033 can include an RF switching period4005 and an uplink signal resource 4006 in the second frame format. Theframe format illustrated in FIG. 8 can be used by the base stationapparatus 1A and the terminal apparatus 2A whose duplex scheme is Timedivision duplex (TDD). The RF switching period 4005 is a period used bythe terminal apparatus that receives a signal transmitted by the basestation apparatus 1A based on the frame format to switch a receptionoperation of the terminal apparatus itself to a transmission operation.The base station apparatus 1A may use the RF switching period 4005 as anon-transmission period, or may transmit any signal (for example, thecommon RS) during the period. Note that, in order to continuouslytransmit the frames generated based on the second frame format, theframe configuration unit 1033 may also provide the RF switching period4005 in the latter half of the uplink signal resource 4006, or can alsoconfigure the non-transmission section between the frames that arecontinuously transmitted. Note that, in a case that the second frameformat is used, the base station apparatus 1A can generate a transmitsignal, with a configuration of the RF switching period 4005 and theuplink signal resource 4006 in the second frame format in a case ofusing the TDD, and without a configuration of the RF switching period4005 and the uplink signal resource 4006 in the second frame format in acase of using FDD, based on each of the second frame formats.

The terminal apparatus 2A that has received the transmit signaltransmitted by the base station apparatus 1A based on the frame formatillustrated in FIG. 8 can arrange information, which indicates receptionpermitted or not permitted (ACK or NACK) relating to a data signaladdressed to the terminal apparatus itself mapped in the data signalresource 4001, in the uplink signal resource 4006, and transmit theinformation to the base station apparatus 1A. Accordingly, the basestation apparatus 1A can immediately grasp whether or not the datasignal addressed to the terminal apparatus 2A is correctly received, andthus a delay time relating to the transmission of the downlink signalcan be reduced.

The frame configuration unit 1033 can define multiple frame formatsincluding the first frame format and the second frame format.Additionally, the frame configuration unit 1033 can define multipleframe formats by changing a radio parameter of the first frame formatand the second frame format. Here, the radio parameters include a partor all of a frequency bandwidth, a center frequency, a frequency band, asubcarrier spacing, the number of subcarriers, a symbol length, anFFT/IFFT sampling cycle, a GI length, a CP length, a frame length, asubframe length, a slot length, a TTI, the number of FFT points, a typeof applied error correcting code (for example, a turbo code is appliedto the first frame format, a low-density parity check code is applied tothe second frame format, and the like), or the like. Additionally, in acase that different radio parameters are configured in the same frameformat, each of the frame formats is also referred to as having adifferent type (mode). For example, in a case that a radio parameter 1and a radio parameter 2 that have different values from each other areconfigured for the first frame formats, the first frame formats can bereferred to as the first frame format type 1 and the first frame formattype 2, respectively. Additionally, the base station apparatus can havea radio parameter set in which each of the values included in the radioparameters is configured beforehand. One or multiple radio parametersets can be configured, by changing the radio parameter sets, the frameconfiguration unit 1033 can configure different frame formats/frameformat types. Additionally, in a case that there are multiple radioparameter sets, each of the radio parameter sets can be configuredthrough a simple rule. For example, in a case that there are three radioparameter sets, the subcarrier spacing of the radio parameter set 2 canbe X times (X is an integer of 2 or more) the subcarrier spacing of theradio parameter set 1, the subcarrier spacing of the radio parameter set3 can be Y times (Y is an integer of 2 or more) the subcarrier spacingof the radio parameter set 2. Note that, some of the parameters includedin each of the radio parameter sets may be a common value. Additionally,the radio parameter set is transmitted (indicated) from the base stationapparatus to the terminal apparatus. At this time, the terminalapparatus can learn of the frame format/frame type by radio parameterset received from the base station apparatus. Note that, hereinafter,unless otherwise stated, even in a case of a frame format, a frameformat type is also included. Additionally, it can be assumed thatwhether or not the terminal is compatible with the above-described radioparameter set depends on a capability of the terminal.

The base station apparatus 1A according to the present embodiment canselectively or simultaneously use the multiple frame formats.Additionally, for the first frame format and the second frame format,the base station apparatus 1A can selectively configure different radioparameters, respectively, or can commonly configure some of them. Thebase station apparatus 1A can notify the terminal apparatus 2A ofinformation indicating the frame format used for a transmit signal bythe base station apparatus itself. Here, the information indicating theframe format includes information indicating any one of multiple frameformats defined by the base station apparatus 1A beforehand (numericalvalue, index, indicator), information indicating resources included inthe frame format (for example, information indicating whether any of thecontrol information resource 4000, the data signal resource 4001, thecommon RS resource 4002, the specific RS resource 4003 is included, ornone of them is included), information indicating a resource where eachof the resources is arranged and a resource candidate having arrangementpossibility, or the like. The base station apparatus 1A can notify theterminal apparatus 2A of at least a part of the information indicatingthe frame format by signalling of a PHY layer, or by higher layersignalling of RRC signalling or the like.

The base station apparatus 1A can use the frame format in a switchingmanner in accordance with a use case (or usage scenario) to which thebase station apparatus itself provides a communication service.Additionally, the base station apparatus 1A can use the radio parameterof the frame format in a changing manner in accordance with the usagescenario to which the base station apparatus itself provides thecommunication service.

In order to satisfy multiple usage scenarios, the base station apparatus1A according to the present embodiment can include a combination ofmultiple frame formats (set, collection), or a combination of multipleradio parameter sets configured for the frame format (set, collection).The base station apparatus 1A can select the frame format among theframe format sets (or combination of the radio parameter sets) preparedbeforehand in accordance with the use case to which the base stationapparatus itself provides the communication service, and generate thetransmit signal transmitted by the base station apparatus itself. Theframe format collection included in the base station apparatus 1A may becommon to the frame format collection included in another base stationapparatus, or may be different. Additionally, the base station apparatus1A can notify the terminal apparatus 2A connected to the base stationapparatus itself of the frame format collection included in the basestation apparatus itself.

The base station apparatus 1A according to the present embodiment canselect multiple transmission modes in a switching manner in order tosatisfy the multiple usage scenarios. Here, the transmission mode isdefined by a combination of a radio parameter, a multiplexing scheme, ascheduling method, a precoding method, or the like that can be used bythe transmission unit 103 of the base station apparatus 1A whengenerating the transmit signal. The frame formats can be allocated tothe multiple transmission modes, respectively. Note that, the frameformats/radio parameters allocated to the multiple transmission modesmay be all different, or some of them may be common. In this case, byselecting the transmission mode, the base station apparatus 1A canselectively use the multiple frame formats/radio parameters.

The base station apparatus 1A can selectively or simultaneously use themultiple frame formats for Enhanced mobile broadband (EMBB), EnhancedMassive machine type communication (EMTC), and Ultra-reliable and lowlatency communication (URLLC) as three usage scenarios. Additionally,the base station apparatus 1A can use the second frame formats withdifferent radio parameters for the EMBB, the EMTC, and the URLLC,respectively. The frame configuration unit 1033 can select the frameformat and determine the radio parameter configured to the frame formatin accordance with the usage scenario to which the base stationapparatus 1A provides the communication service.

For example, the base station apparatus 1A can generate the frame basedon the first frame format for the downlink signal relating to the EMBB,and generate the frame based on the second frame format for the downlinksignal relating to the MMTC and the URLLC. Although, in this method, thebase station apparatus 1A switches the frame format in accordance withthe use case (or usage scenario) to which the base station apparatusitself provides a communication service, in the method according to thepresent embodiment, the frame format is not necessarily limited to bedefined for each use case.

The base station apparatus 1A can selectively or simultaneously use themultiple frame formats/radio parameters based on a radio medium throughwhich the base station apparatus itself transmits the downlink signal.Here, the radio medium can include a radio resource such as a timeresource, a frequency resource, or the like. Additionally, the radiomedium can include a radio resource that is distinguished by a duplexscheme applied to a frequency band in which the base station apparatus1A transmits the downlink signal.

Additionally, the radio medium can include a radio resource that isdistinguished in accordance with the use case (or usage scenario) towhich the base station apparatus 1A provides the communication service.The base station apparatus 1A can select the radio medium to be used inaccordance with the use case (or usage scenario) provided with thecommunication service. The base station apparatus 1A can determinebeforehand the radio medium to be used when providing the communicationservice to each use case (or usage scenario). Accordingly, the radiomedium and the use case are associated with each other, the base stationapparatus 1A can selectively or simultaneously use the multiple frameformats/radio parameters based on which use case (or usage scenario) theradio medium to be used is associated with.

The base station apparatus 1A can notify the terminal apparatus 2A ofinformation indicating the multiple frame formats/radio parameters thatare selectively or simultaneously used by the PHY layer/MAC layer or ahigher layer signalling such as RRC signalling or the like based on theradio medium to which the base station apparatus itself transmits thedownlink signal. Note that, the base station apparatus 1A may notnecessarily notify the terminal apparatus 2A of all the informationindicating the above-described multiple frame formats/radio parameters.For example, the base station apparatus 1A can notify the terminalapparatus 2A of candidates of the above-described multiple frameformats/radio parameters. In the terminal apparatus 2A, the informationindicating the multiple frame formats/radio parameters that areselectively or simultaneously used by the base station apparatus 1Abased on the radio medium can be subjected to signalling through theabove-described method by the base station apparatus 1A, or theinformation can be partially and blindly detected. Note that, theterminal apparatus 2A can notify the base station apparatus 1A ofinformation relating to the above-described multiple frame formats/radioparameters that can be received by the terminal apparatus itself.

The base station apparatus 1A can selectively or simultaneously use themultiple frame formats/radio parameters in accordance with a frequency(frequency band, channel) with which the downlink signal is transmitted.For example, the base station apparatus 1A can separate the frequencieswith which the downlink signal can be transmitted into multiple groups.For example, by setting frequencies of lower than 6 GHz (Below 6 GHz) asa frequency band 1 and setting frequencies of 6 GHz or higher (Above 6GHz) as a frequency band 2, the base station apparatus 1A can switch theframe format between a case of transmitting the downlink signal in thefrequency band 1 and a case of transmitting the downlink signal in thefrequency band 2 and use it. Additionally, by setting frequencies oflower than 2 GHz as a frequency band 1, setting frequencies of 2 GHz orhigher and lower than 6 GHz as a frequency band 2, and settingfrequencies of 6 GHz or higher as a frequency band 3, the base stationapparatus 1A can generate a transmit signal based on the frame formatdefined by each of the frequency bands in a case of transmitting thedownlink signal in each of the frequency bands.

The base station apparatus 1A can simultaneously transmit signalsgenerated based on different frame formats/radio parameters. FIG. 9 is aschematic diagram illustrating a configuration example of a downlinksignal transmitted by the base station apparatus 1A according thepresent embodiment. According to the example in FIG. 9, the base stationapparatus 1A uses different frame formats in accordance with thefrequencies. The base station apparatus 1A can mix the multipledifferent frame formats in one OFDM signal. For example, multiplesubcarriers constituting the one OFDM signal are divided into multiplesubcarrier groups, the transmit signal mapped in each of the subcarriergroups is generated based on each of the different frame formats. Notethat, according to the example in FIG. 9, the second frame formatincludes the RF switching period 4005 and the uplink signal resource4006. Accordingly, the base station apparatus 1A can generate a signalbased on the first frame format and a signal based on the second frameformat by the different OFDM signals, respectively, and canfrequency-multiplex and simultaneously transmit the different OFDMsignals.

Note that, according to the example in FIG. 9, although the subcarriergroup generated based on the first frame format and the subcarrier groupgenerated based on the second frame format are adjacent to each other,the frame configuration unit 1033 can also arrange a guard band (nullsubcarrier, non-transmission frequency) between the subcarrier groups.Additionally, according to the example in FIG. 9, although frame lengthsof the signals transmitted in the subcarrier group generated based onthe first frame format and transmitted in the subcarrier group generatedbased on the second frame format, respectively, are the same, the framelengths of the signals may be different from each other. Note that,however, from the standpoint of synchronization in a radio network, arelationship between the frame lengths of the signals respectivelytransmitted in the subcarrier groups is preferably a relationship of anintegral multiple.

Additionally, the transmission unit 103 of the base station apparatus 1Acan generate a filtered OFDM signal to which a filter is applied foreach of the subcarriers, or for each of the subcarrier groups configuredof multiple subcarriers. The filtered OFDM can be, for example, a Filterbank multicarrier, or Filtered OFDM. In the filtered OFDM, interferencebetween the subcarriers (or between the subcarrier groups) is largelysuppressed. The base station apparatus 1A can allocate different frameformats to multiple subcarrier groups generated by the base stationapparatus itself, respectively. For example, the transmission unit 103of the base station apparatus 1A can generate a first subcarrier groupbased on the first frame format, generate a second subcarrier groupbased on the second frame format, and generate the Filtered OFDM signalincluding the first subcarrier group and the second subcarrier group.

The base station apparatus 1A can define the frame format for eachduplex scheme. For example, the base station apparatus 1A can define thedifferent frame formats for a case of the FDD and a case of the TDD,respectively. The base station apparatus 1A can generate the transmitsignal based on the first frame format in a case of the FDD, and, on theother hand, can generate the transmit signal based on the second frameformat in a case of the TDD.

Additionally, the base station apparatus 1A can selectively use themultiple frame formats in one duplex scheme. For example, the basestation apparatus 1A can selectively or simultaneously use the firstframe format and the second frame format in a case using the FDD as theduplex scheme. Additionally, the base station apparatus 1A canselectively or simultaneously use the multiple radio parameters for thefirst frame format (or the second frame format) in one duplex scheme.

Additionally, the base station apparatus 1A can use the duplex scheme inwhich the FDD and the TDD coexist, and the base station apparatus 1A candefine the frame format for the duplex scheme in which the FDD and theTDD coexist. Additionally, the base station apparatus 1A can selectivelyor simultaneously use the multiple frame formats or the radio parametersin the duplex scheme in which the FDD and the TDD coexist. As the duplexscheme in which the FDD and the TDD coexist, the base station apparatus1A can use the duplex scheme that temporally switches the FDD and TDD bythe frequency band. As the duplex scheme in which the FDD and the TDDcoexist, the base station apparatus 1A can use Full duplex (orSimultaneous transmission and reception (STR)) that simultaneouslyperforms the uplink transmission and the downlink transmission. In theSTR, the base station apparatus 1A and the terminal apparatus 2A cansimultaneously transmit the transmit signals generated based ondifferent frame formats, respectively.

For the radio parameters configured to the first frame format and thesecond frame format, the base station apparatus 1A can configuredifferent radio parameters between a case that the frequency band inwhich the transmit signal generated based on each of the frame formatsis transmitted is a frequency band that is a so-called licensed band forwhich a radio operator obtains use permission (license) from a countryor region in which the radio operator provides the service and a casethat the frequency band is a frequency band that is a so-calledunlicensed band that does not require the use permission from thecountry or region.

For the radio parameters configured to the first frame format and thesecond frame format, in a case that the frequency band in which thetransmit signal generated based on each of the frame formats istransmitted is the unlicensed band, the base station apparatus 1A canchange the radio parameter to be configured in accordance with thefrequency band of the unlicensed band. For example, the base stationapparatus 1A can change the radio parameter between a case that theunlicensed band in which the transmit signal is transmitted is a 5 GHzband and a case that the unlicensed band is a 60 GHz band.

The base station apparatus 1A can use a frame format that can beobtained by extending an occupied frequency bandwidth of the frameformat used in the unlicensed band of 5 GHz band to an integral multiplefor the unlicensed band of 60 GHz band. Additionally, the base stationapparatus 1A binds multiple transmit signals generated by the frameformat used for the licensed band of 6 GHz or higher in the frequencydomain, and can use it for the unlicensed band of 60 GHz band. By onlythe base station apparatus itself and cooperating with another basestation apparatus, the base station apparatus 1A can simultaneouslytransmit multiple component carriers generated based on the frame formatused for the licensed band of 6 GHz or higher by the Carrier Aggregation(CA) and the Dual Connectivity (DC), while arranging in the unlicensedband of 60 GHz band, to the terminal apparatus 2A.

The base station apparatus 1A can use, in the unlicensed band of 60 GHzband, a frame format with a bandwidth that is the same as a channelbandwidth defined by IEEE802.11ad (for example, 2 GHz or 2.16 GHz) orwith a bandwidth that is an integral multiple of the bandwidth.Additionally, the base station apparatus 1A can use a frame format forthe unlicensed band of 60 GHz band or the licensed band of 6 GHz orhigher, an integral multiple of (including a case of equal to) thefrequency bandwidth of the frame format matching the channel bandwidthdefined by IEEE802.11ad.

For the radio parameters configured to the first frame format and thesecond frame format, the base station apparatus 1A can configuredifferent radio parameters between a case that the frequency band inwhich the transmit signal generated based on each of the frame formatsis transmitted is an occupied frequency band that can be exclusivelyused by one radio operator and a case that the frequency band is ashared frequency band (Shared band) that is shared and used by multipleradio operators.

The base station apparatus 1A can map multiple transmit signalsgenerated based on different frame formats in the frequency domain. In acase that the multiple transmit signals generated based on the differentframe formats are mapped in the frequency domain, the base stationapparatus 1A can simultaneously transmit the multiple transmit signalsby the carrier aggregation (CA) in which multiple component carriers(CC) are aggregated and transmitted. Note that, the multiple CCstransmitted by the carrier aggregation can be transmitted from themultiple different base station apparatuses. Additionally, in thecarrier aggregation, one Primary Cell (PCell) and one or multipleSecondary Cells (SCell) are configured as a set of the serving cells.

The base station apparatus 1A can use the different frame formats/radioparameters for the multiple CCs transmitted by the CA, respectively. Forexample, in a case of performing CA transmission of two CCs, the basestation apparatus 1A can apply the first frame format to a first CC, andapply the second frame format to a second CC. Additionally, the basestation apparatus 1A can generate a transmit signal transmitted by eachCC based on the second frame format in which different radio parametersare configured. In other words, the base station apparatus 1A canconfigure the frame format/radio parameter for each cell. For example,the base station apparatus 1A can communicate by the first frame formatin the PCell/SCell, and communicate by the second frame format in theSCell. Additionally, although the base station apparatus 1A communicateby the second frame format in the PCell and the SCell, the radioparameters to be configured can be made different for each cell.

The base station apparatus 1A can include information indicating theframe format configured to the CC to be the secondary cell in controlinformation arranged in the control information resource 4000 includedin the CC to be the primary cell.

In a case that the multiple transmit signals generated based on thedifferent frame formats are mapped in the frequency domain, the basestation apparatus 1A can transmit the transmit signals by the Dualconnectivity (DC) that simultaneously transmit the signals from multipletransmission points, while cooperating with another base stationapparatus. In the DC, as a group of the serving cells, a Master CellGroup (MCG) and a Secondary Cell Group (SCG) are configured. The MCG isconfigured of the PCell and optional one or multiple SCells.Additionally, the SCG is configured of a primary SCell (PSCell) andoptional one or multiple SCells. For example, in a case that the basestation apparatus 1A and a base station apparatus 1B transmit thedownlink signals to the terminal apparatus 2A by the DC, the basestation apparatus 1A and the base station apparatus 1B can generatetransmit signals based on the different frame formats/radio parametersand transmit the generated signals, respectively. Additionally, in acase that the base station apparatus 1A and the base station apparatus1B transmit the downlink signals to the terminal apparatus 2A by the DC,the base station apparatus 1A and the base station apparatus 1B cangenerate transmit signals based on the second frame formats in whichdifferent radio parameters are configured and transmit the generatedsignals, respectively. In other words, the base station apparatus 1A canconfigure the frame format/radio parameter for each cell. For example,the frame formats that are different between the PCell and the PSCellare configured, and the frame formats that are different between thePCell/PSCell and the SCell are configured. Additionally, the basestation apparatuses 1A/1B can configure the second frame format in whichthe radio parameters that are different between the PCell and the PSCellare configured.

The base station apparatus 1A can notify the terminal apparatus 2A ofinformation relating to the frame formats/radio parameters configured tothe multiple downlink signals mapped in the frequency domain,respectively. In a case of the CA or the DC, the base station apparatus1A can transmit information relating to the frame format/radio parameterconfigured for each cell to the terminal apparatus 2A.

The base station apparatus 1A can map multiple transmit signalsgenerated based on different frame formats/radio parameters in a spacedirection. For example, in a case of simultaneously transmitting thedownlink signals to the terminal apparatus 2A and the terminal apparatus2B, by multiuser multiple-input and multiple-output transmission(MU-MIMO), the base station apparatus 1A can generate the transmitsignal addressed to the terminal apparatus 2A and the transmit signaladdressed to the terminal apparatus 2B based on different frame formats,respectively, and transmit the two transmit signals while spatiallymultiplexing. In other words, the transmit signal transmitted by thebase station apparatus 1A according to the present embodiment can besuch that transmit signals generated based on the frame formats that aredifferent in the space direction are spatially multiplexed.

In a case that the base station apparatus 1A multiplexes the transmitsignals generated based on the different frame formats in the spacedirection, the base station apparatus 1A can make, for each of the frameformats, at least a part of the resource where the specific RS resource4003 is arranged as a common resource.

Additionally, in a case that the terminal apparatus 2A includes afunction for removing or suppressing interference between users orinterference between neighbor cells, the base station apparatus 1A cantransmit assist information for removing or suppressing the interferencebetween the users or the interference between the neighbor cells. Theassist information (neighbor cell information) includes a part or all ofa physical cell ID, the number of CRS ports, a PA list, PB, a MultimediaBroadcast multicast service Single Frequency Network (MBSFN) subframeconfiguration, a transmission mode list, a resource allocationgranularity, a UL/DL subframe configuration of TDD, a ZP/NZP CSI-RSconfiguration, quasi co-location (QCL) information, a frame format, anda radio parameter. The PA is a power ratio (power offset) of the PDSCHand the CRS in an OFDM symbol where the CRS is not allocated. The PBrepresents a power ratio (power offset) of the PDSCH in the OFDM symbolwhere the CRS is allocated and the PDSCH in the OFDM symbol where theCRS is not allocated. The QCL information is information relating to theQCL for a prescribed antenna port, a prescribed signal, or a prescribedchannel. In a case that, in two antenna ports, long duration performanceof a channel on which a symbol is carried on one antenna port can beestimated from a channel on which a symbol is carried on the otherantenna port, these antenna ports are called the QCL. The long durationperformance includes delay spread, Doppler spread, Doppler shift,average gain and/or average delay. In other words, in a case that thetwo antenna ports are the QCL, the terminal apparatus can consider thatthese antenna ports have the same long duration performance. Note that,in each of the parameters included in the assist information, one value(candidate) may be configured, or multiple values (candidates) may beconfigured. In the case of multiple values being configured, for theparameters, the terminal apparatus interprets values being indicatedthat has a possibility of being configured by the base station apparatuscausing interference, and detects (specifies) a parameter configured inthe interference signal among the multiple values. Additionally, theabove-described assist information may indicate information of anotherbase station apparatus/beam, or may indicate information of the basestation apparatus itself/beam. In addition, the above-described assistinformation may be used in a case that various types of measurement arecarried out. The stated measurement includes Radio Resource Management(RRM) measurement, Radio Link Monitoring (RLM) measurement, and ChannelState Information (CSI) measurement.

2. Common to All Embodiments

Note that, the base station apparatus and the terminal apparatusaccording to an aspect of the present invention are not limited to beused in a Radio access technology (RAT) operated with the licensed band,and can be used in the Radio access technology operated with theunlicensed band. Additionally, the RAT operated with the unlicensed bandcan be a licensed assisted access that can receive an assistance of thelicensed band.

Additionally, the base station apparatus and the terminal apparatusaccording to an aspect of the present invention can be used in the Dualconnectivity (DC) in which signals are transmitted from (or received by)multiple transmission points (or multiple reception points). The basestation apparatus and the terminal apparatus can be used forcommunication with at least one of the multiple transmission points (orreception points) connected with the DC. Additionally, the base stationapparatus and the terminal apparatus according to an aspect of thepresent invention can be used in the carrier aggregation (CA) in whichmultiple component carriers (CCs) are used. Among the multiple CCssubjected to the CA, the base station apparatus and the terminalapparatus can be used for only the primary cell, can be used for onlythe secondary cell, or can be used for both the primary cell and thesecondary cell.

A program running on each of the base station apparatus and the terminalapparatus according to an aspect of the present invention is a program(a program for causing a computer to operate) that controls a CPU andthe like in such a manner as to realize the functions according to anaspect of the above-described embodiments of the present invention. Theinformation handled by these devices is temporarily held in a RAM at thetime of processing, and is then stored in various types of ROMs, HDDs,and the like, and read out by the CPU as necessary to be edited andwritten. Here, a semiconductor medium (a ROM, a non-volatile memorycard, or the like, for example), an optical recording medium (DVD, MO,MD, CD, BD, or the like, for example), a magnetic recording medium (amagnetic tape, a flexible disk, or the like, for example), and the likecan be given as examples of recording media for storing the programs. Inaddition to realizing the functions of the above-described embodimentsby executing loaded programs, the functions of the present invention arerealized by the programs running cooperatively with an operating system,other application programs, or the like in accordance with instructionsincluded in those programs.

In a case that delivering these programs to market, the programs can bestored in a portable recording medium, or transferred to a servercomputer connected via a network such as the Internet. In this case, thestorage device serving as the server computer is also included in thepresent invention. Furthermore, some or all portions of each of theterminal apparatus and the base station apparatus in the above-describedembodiments may be realized as LSI, which is a typical integratedcircuit. The functional blocks of the reception device may beindividually realized as chips, or may be partially or completelyintegrated into a chip. In a case that the functional blocks areintegrated into a chip, an integrated circuit control unit forcontrolling them is added.

The circuit integration technique is not limited to LSI, and theintegrated circuits for the functional blocks may be realized asdedicated circuits or a multi-purpose processor. Furthermore, in a casethat with advances in semiconductor technology, a circuit integrationtechnology with which an LSI is replaced appears, it is also possible touse an integrated circuit based on the technology.

It is to be noted that the invention of the present patent applicationis not limited to the above-described embodiments. The terminalapparatus according to the invention of the present patent applicationis not limited to the application in the mobile station device, and,needless to say, can be applied to a fixed-type electronic apparatusinstalled indoors or outdoors, or a stationary-type electronicapparatus, for example, an AV apparatus, a kitchen apparatus, a cleaningor washing machine, an air-conditioning apparatus, office equipment, avending machine, and other household apparatuses.

The embodiments of the invention have been described in detail thus farwith reference to the drawings, but the specific configuration is notlimited to the embodiments. Other designs and the like that do notdepart from the essential spirit of the invention also fall within thescope of the claims.

INDUSTRIAL APPLICABILITY

The present invention can be preferably used in a base stationapparatus, a terminal apparatus, and a communication method.

The present international application claims priority based on JP2016-012184 filed on Jan. 26, 2016, and all the contents of JP2016-012184 are incorporated in the present international application byreference.

DESCRIPTION OF REFERENCE NUMERALS

-   1A, 1B Base station apparatus-   2, 2A, 2B Terminal apparatus-   101 Higher layer processing unit-   1011 Radio resource control unit-   1012 Scheduling unit-   102 Control unit-   103 Transmission unit-   1031 Coding unit-   1032 Modulation unit-   1033 Frame configuration unit-   1034 Multiplexing unit-   1035 Radio transmission unit-   104 Reception unit-   1041 Radio reception unit-   1042 Demultiplexing unit-   1043 Demodulation unit-   1044 Decoding unit-   105 Antenna-   201 Higher layer processing unit-   202 Control unit-   203 Transmission unit-   204 Reception unit-   205 Channel state information generating unit-   206 Antenna-   2011 Radio resource control unit-   2012 Scheduling information interpretation unit-   2031 Coding unit-   2032 Modulation unit-   2033 Frame configuration unit-   2034 Multiplexing unit-   2035 Radio transmission unit-   2041 Radio reception unit-   2042 Demultiplexing unit-   2043 Signal detection unit-   4000 to 4007 Resource-   5000 Subframe

1. A base station apparatus for communicating with a terminal apparatus,the base station apparatus comprising: a transmission unit configured togenerate a transmit signal based on a frame format in which a radioparameter is configurable, and configured to notify the terminalapparatus of information indicating the radio parameter configured inthe frame format.
 2. The base station apparatus according to claim 1,wherein the frame format includes a common reference signal resource anda data signal resource, and the common reference signal resource and thedata signal resource are sequentially arranged in a time domain.
 3. Thebase station apparatus according to claim 2, wherein the transmissionunit generates the transmit signal based on a frame format in which atleast one resource included in the frame format is subjected toaggregation in the time domain or a frequency domain.
 4. The basestation apparatus according to claim 3, wherein the transmission unitprovides a non-transmission section to the transmit signal generatedbased on the frame format including the aggregation.
 5. The base stationapparatus according to claim 1, wherein the transmission unitselectively or simultaneously uses a first frame format having adifferent resource arrangement from a resource arrangement of the frameformat and a second frame format being the frame format to generate thetransmit signal.
 6. The base station apparatus according to claim 1,wherein the radio parameter includes a subcarrier spacing.
 7. The basestation apparatus according to claim 3, the base station apparatustransmits a configuration relating to the aggregation to the terminalapparatus.
 8. A terminal apparatus for communicating with a base stationapparatus, the terminal apparatus comprising: a reception unitconfigured to acquire information indicating a radio parameterconfigured in a frame format, and configured to demodulate a signalgenerated based on the frame format, based on the radio parameter. 9.The terminal apparatus according to claim 8, wherein the signaldemodulated by the reception unit is generated by selectively orsimultaneously using a first frame format having a different resourcearrangement from a resource arrangement of the frame format and a secondframe format being the frame format.
 10. The terminal apparatusaccording to claim 9, wherein the reception unit performs blinddetection for whether the signal is generated based on the first frameformat or generated based on the second frame format.
 11. The terminalapparatus according to claim 10, wherein a method of the blind detectionis a synchronization processing method performed by the reception unitor an acquiring method of a broadcast signal performed by the receptionunit.
 12. A communication method of a base station apparatus forcommunicating with a terminal apparatus, the communication methodcomprising the steps of: generating a transmit signal based on a frameformat in which a radio parameter is configurable; and notifying theterminal apparatus of information indicating the radio parameterconfigured in the frame format.
 13. A communication method of a terminalapparatus for communicating with a base station apparatus, thecommunication method comprising the steps of: acquiring informationindicating a radio parameter configured in a frame format; anddemodulating a signal generated based on the frame format, based on theradio parameter.